竹笋生长期营养及安全品质的分析

Nutritional and Safety Evaluation of Unearthed Bamboo Shoots during Growth

目的:了解竹笋出土后高生长过程中营养及安全品质的变化规律。方法:选取栽培条件一致的竹林,从竹笋即将露土开始标记,选取同一天标记的竹笋在不同生长高度采收,分析测试其营养及安全指标。结果:竹笋生长期粗蛋白含量基本呈下降的趋势,随高生长以0.017mg/(kg.cm)而下降;蛋白质中必需氨基酸所占比例在递增;粗纤维含量没有太大的变化;笋体内硝酸盐含量最高为175mg/kg,亚硝酸盐最高为84mg/kg;露土高度5～15cm范围内,硝酸盐和亚硝酸盐的含量均低于10mg/kg。结论:竹笋在出土后高生长过程中营养价值在提高,笋体内的硝酸盐积累少,是较安全的。

Purpose： To understand changes in nutrient and hazardous substances during the growth of unearthed bamboo shoots.Methods： The starting point of the growth period of bamboo shoots from selected bamboo forests under the same cultivation conditions was just before breaking through the soil.Unearthed bamboo shoots with different heights labeled on the same day were harvested and analyzed for their nutrients and hazardous substances.The results revealed that crude protein content basically tended to decrease during the growth of bamboo shoots and decreased by 0.017 mg/（kg·cm） with increasing height.The proportion of essential amino acids occupying total amino acids displayed a gradual increase.No obvious change in crude fiber content was observed.The maximum content of nitrate in bamboo shoots was 175 mg/kg.In the height range of 5 to 15 cm,both nitrite and nitrate contents were less than 10 mg/kg.Conclusion： The nutritional value of unearthed bamboo shoots increases with the extension of growth period,and a very small amount of nitrite is accumulated.Therefore,higher bamboo shoots are a nutritional and safe food.